Ibuprofen (IBU), a common pharmaceutical and personal care product (PPCP), is a pervasive water pollutant with adverse ecological and human health effects after transformation and accumulation. In this study, we synthesized Fe, N-doped carbon quantum dots (Fe, N-CQDs) using pig blood and FeCl3 as a precursor via a one-step hydrothermal method. TEM, XRD, XPS, and UV–Vis were used to characterize the physical and chemical properties of Fe, N-CQDs. We investigated the feasibility of Fe, N-CQDs in activating peroxymonosulfate (PMS) for IBU degradation under visible light. The experimental results revealed that Fe in Fe, N-CQDs predominantly formed a stable complex through Fe–N and Fe-OH, with a high degree of graphitization and a sp2- hybridized graphitic phase conjugate structure. The Fe, N-CQDs/Light/PMS system exhibited strong activity, degrading over 87% of IBU, maintaining a wide pH range (3–10) adaptability. Notably, Fe, N-CQDs acted as visible-light catalysts, promoting Fe3+/ Fe2+ cycling and PMS activation, generating both free radicals ( SO4 •–, ·OH) and non-radicals (1O2, h+) to effectively degrade IBU. This study presents an innovative approach for the sustainable utilization of pig blood as a biomass precursor to synthesize Fe- and N-doped carbon materials. This study provides a new approach for the sustainable and value-added utilization of natural wastes and biomass precursors of Fe- and N-doped carbon materials, which can be used to treat pollutants in water while treating discarded pig blood.